Originally published as an alumni profile by the Association of Accredited Naturopathic Medical Colleges.
From his father, renowned naturopath Dr. Peter J. D’Adamo inherited the notion that people of different blood types do better on certain diets. Years of validating and synthesizing the science behind the idea culminated in the 1996 award-winning book Eat Right 4 Your Type. The bestseller was followed by a series of books on the connections between blood type and many of our nation’s most serious health problems, including diabetes, cancer and heart disease.
Then in 2007, Dr. D’Adamo published The GenoType Diet, offering a therapeutic series of diets for six different genotypes. Building on blood type, the book explores the concept of epigenetics - the way in which our genes respond to our environment and create differences that we then pass along to our children. Recently, Dr. D’Adamo has developed a software program that generates a personalized, unique diet for each of his patients. He has also opened a personalized nutrition store in Connecticut.
The validation of an idea
AANMC: What was it like growing up under the influence of your father, James D’Adamo, who began the research on blood types as they relate to diet? Did you grow up eating for your type?
PD: Naturopathic principles were part of the way I was brought up; we managed to treat illnesses fairly naturally. Growing up in Brooklyn, I’d say we ate more healthfully than average. At that time, about the only thing that was certain in my dad’s work was that A’s did better on a plant-based diet. Dad is type A, and he’s a vegetarian. I am also an A, and I’ve maintained a sort of quasi-vegetarian diet most of my life.
AANMC: How is your relationship with your dad today? You are both authors and experts. Is there a little professional competition between the two of you?
PD: Not really. What you see with me and my dad is a classic example of what happens when a profession changes. My dad’s work was empirical and practiced in tremendous isolation. Most naturopaths of his generation came from a naturopathic/chiropractic bent - they were really both, and the naturopathic aspect was mostly an enhancement of the chiropractic. The second generation, initiated by naturopathic doctors like Pizzorno and Mitchell, was much more focused on pure biochemistry and pharmacology and the idea that this type of medicine could be validated through scientific methods.
The blood type diet theory was big enough that it really required the work of two lives. It needed a pure, traditional naturopath to even conceive of looking at things that way. I think the blood type diet was an astounding leap of consciousness that really had to come from the mind of a naturopath, because we spend so much time trying to find the discrete differences between people. Then the theory required a second generation to call it into question and see if it was verifiable, and that process opened up yet another series of opportunities. To this day, that’s what I enjoy most - finding cyclical, scientific references to the ideas found in traditional sources, and giving a different type of imprimatur to what those guys (naturopaths of earlier generations) were doing.
There are hundreds, if not thousands, of articles that support all the contentions I’ve ever made in my books. And I’ve made it all available online. On my Eat Right 4 Your Type Web site, people have reported a 75 to 81 percent success rate for the blood type diet over the years - and that’s across the board. A type A on a vegetarian diet reports about the same amount of success as a type O on a low carb diet.
AANMC: Did you have the idea for your research when you attended naturopathic medical school?
PD: When I was at Bastyr, my father had written a book called One Man’s Food, which contained his observations. People in my profession would ask, “Why isn’t it referenced?” But my father is the kind of person who goes ahead and types 5,000 people’s blood and observes who does well on what diet. That’s his research. Up to that point, what I had been taught about blood transfusions and other aspects of blood typing didn’t give me any information that supported my father’s ideas about how people should eat. To this day, I understand how some people can be incredulous of the theory; given what I was taught in school about blood groups, I was incredulous as well.
But I did have one teacher, Dr. Ed Madison, who said “I wish your father had made mention of the reference between blood types and ulcers, since that would have pointed to digestive tract differences.” I said, “Well, there we go. Let me go pull up everything I can find that looks at illnesses and blood type. And if my father’s right, the type A’s should have illnesses associated with eating meat, because he said they shouldn’t consume that.” It was no surprise when I found that a lot of health problems associated with excessive animal protein consumption, like heart disease, cancer and vascular disorders, were much more common in type A’s. On the other hand, one of the things I discovered in the early ‘80s was that type O’s didn’t do so well on carbohydrates, which indirectly validated the Atkins and Zone diets. And it turned out to be more than that. A lot of the grains and beans have properties called agglutinins or lectins. About half of these foods have some specificity for one blood type or another. So by the mid-80s, I was looking at the immunological effects of foods on people that could be predicted by knowing the components of the food and their actions on the molecules that determine blood type. It’s as simple as A is to B as B is to C.
Food as medicine
AANMC: Would you say that food is one of the primary medicines available to humans?
PD: Food is great because it lets people amortize problems over time, problems that no doctor can fix. For example, a patient comes in and tells me he’s got a migraine. I give him feverfew, and hopefully the migraine goes away - end of story. But has it really made a change in his life? Have I done anything to address where that person is coming from? Where they are going? That’s the aspect of epigenetics that’s so exciting! By looking at a person’s past, you can synthesize that information and come up with an approximation of what’s going to happen in the future. It’s like if a cannonball lands at my feet. I don’t know much about it, other than the fact that it nearly killed me. But if I study the cannonball, the wind direction and some other things, I can predict where that cannonball came from with reasonable certainty. Gene expression follows the same pattern. The genetics that we typically focus on in medicine are rapidly becoming irrelevant. We look at gene mutations, but people don’t change that way. People respond to their environments by changing the expression of their genes, not by altering the genes themselves. For instance, if you ever smoked a cigarette as a teenager, it was a very unpleasant experience initially. But if your friends keep encouraging you and you keep smoking, it gradually turns into a pleasurable pastime and finally an addiction. What’s changed? You’ve turned on genes in your liver that help you detoxify nicotine. That’s a classic example of a gene expression alteration based on an environmental challenge.
AANMC: How does it feel to be a vegetarian recommending a meat-based diet to many of your patients?
PD: When I studied at Bastyr, almost everybody on the faculty supported vegetarianism. The first course of action was typically to put a patient on a vegetarian diet, and if that didn’t work maybe test for allergies and try a rotation diet. In my experience, most of these patients didn’t become much healthier. Even through my first seven years of practice, I was trying to figure out the offending food. Then one day, a patient cancelled and I was daydreaming, and it suddenly hit me: I was devoting all my inquisitive energy to finding out what I should eliminate from people’s diets, but I should have been devoting my energy to determining what they should consume! After that, identifying the super foods, the “beneficials,” became the holy grail for me. If you just relax and realize that there’s no such thing as a good or bad diet, then you can design a diet specific to that person, and he or she becomes a lot healthier.
For example, a dietician would say that a high-protein diet takes the calcium off your bones. The theory is that protein increases acidity, and the body buffers acidity with calcium, which often comes from bones. However, type O’s possess an enzyme that is activated when protein is consumed, allowing the body to absorb calcium. So for at least for 44 percent of the population, the theory that a high-protein diet equals loss of calcium is incorrect. A type O’s ability to split cholesterol is also activated by eating protein. When you put a type O on the O diet, his immunity parameters change in ways not normally associated with diet alteration – the thyroid, psoriasis and rheumatoid arthritis are all affected.
Now if you eat red meat and you’re a type A, you don’t have the enzyme that enhances calcium absorption or the ability to split cholesterol effectively. On the other hand, a type A’s body is custom made for soy protein. This group of people is prone to cancer, and the cancers often look like the blood type. If you’ve got a cancer that looks like you, that’s a bad thing. But the proteins in soy are wonderful in their ability to identify things that are mimicking type A blood. That’s something you never hear discussed - the fact that these proteins are able to alert a person’s immune system to elements that are attempting to take advantage of a similarity between them and the person’s blood type.
AANMC: Will you share a story about how your practice of naturopathic medicine has helped one of your patients?
PD: I could tell you thousands. A patient who also helped me with my Web site suffered from a disease called Pemphigus. It’s an autoimmune disease of the mucus membranes in your skin. It causes blisters, it’s messy, and then you die. He was the head of a vegetarian society and a three-time national vegetarian trivia contest winner. He was getting sicker and sicker, and all his vegetarian friends were telling him he wasn’t being a good enough vegetarian. At one point he read my book, and he said “I don’t like the idea, but I just refuse to die for the cause.” He changed his diet to include meat and put his Pemphigus into remission. Years later, he told me that his gluteal muscles, which had been destroyed by all the steroids he had taken, had come back too. You guessed it - he was type O! That’s the power of being flexible in your food choices!
And sometimes, even when you fail you succeed. One of my dearest patients passed away from breast cancer after 11 years. During her illness, her oncologist would roll his eyes when she would come to me for treatments. But then at the end, he said, “If it wasn’t for the other guy, this would have happened years ago.”
I tell students it’s simple. You’ve got a person on one side of the river, and you’ve got to get him to the other side. If he gets there, you win. You try one thing, and if that doesn’t work, you try something else. A type A with cancer is going to be difficult. In a type A person, cancer tends to be a bit more aggressive and more inclined to metastasize. When dealing with type A breast cancer patients who want alternative treatment, I’ve taken a lot of different approaches. I’ve said, “You’ve got to go back and get some conventional treatment first.” I’ve sent patients back to their oncologists and said, “I think you should do a more aggressive chemotherapy protocol.” And to some patients, who’ve wanted to avoid chemotherapy, I’ve said “OK, I can go along with that.” It’s paradoxical, but the key is to have a full 360 degree mindset in approaching each individual patient. Back to top
To infinity and beyond!
AANMC: What are some of your newest endeavors?
PD: We have a professional association, Institute for Human Individuality (IFHI), and we put on a biannual conference to certify professionals in nutrigenomic medicine. We’ve done it with Southwest College of Naturopathic Medicine (SCNM) for the last couple of years, and this year we did it at the University of Bridgeport (UB), just ten miles from my office.
In August 2009, I will start a personalized medicine clinic rotation shift at the UB Naturopathic Medical Clinic. It’s a combination of the work I’ve done with the GenoType Diet and other areas of blood type. My students will be learning about the different inventories I use to assess the epigenotypes of the patients. And then, in combination with blood group information, we will insert the data into software that I’ve written. The results are unique, one-of-a-kind diets. So I will be teaching students to move nutrition to the forefront of their practices. You’d be surprised how few naturopaths are actively involved in using nutrition in this way.
I use the term “intergenerational medicine.” In your body, 70 percent of the genes have little volume controls, and they’re constantly affected by your environment. If you twiddle them one way, you get diabetes. If you twiddle them another, you get Alzheimer’s. The amazing thing is that the settings on the genes are as inheritable as the genes themselves. And the setting on a given gene is influenced by prenatal state, prenatal nutrition, family history, first few years of life and diet. The UB Clinic serves a lot of low income patients, so it’ll be great to get this information into the hands of people without a lot of money.
I also have a big interest in bioinformatics, and I write a lot of software. The professional version of the SWAMI GenoType software was released in June 2009. I’m trying to get younger naturopaths comfortable with using these tools to answer questions - not just by using other people’s software, but by using computer language itself.
And we’ve just opened a personalized nutrition store. It’s an anomaly. We make supplements based on some of my work, so we offer seven multivitamins and six different minerals for the various genotypes and blood types. We have a dilemma that is very much like that of the Apple computer. We can’t find a context for ourselves in a conventional health food store. So we took a page from Apple’s book, and we did it on our own.
AANMC: How do you do all that and see patients too?
PD: I start my day at about 4 AM. I’m like a buzz saw for about four hours, and that’s usually when I do all the high-level, research-oriented stuff. Then I shower, eat breakfast and go into to the clinic for about five hours. At the clinic, I use a different type of intelligence that mostly relies on what I already know. It’s almost like there are two sides of me. The early part tries to see what’s invisible, while the midday part just tries to see what’s visible. Then the third part of my day is spent with my family and getting things in order as needed. I go to bed fairly early. I’m one of those people who jumps out of bed with a solution to a problem. So I think that even when I’m sleeping, I’m working.
AANCM: Not everyone practicing naturopathic medicine will be a bestselling author. What is your message to someone considering becoming an ND?
PD: My father thought I should have been a medical doctor, because he had been harassed his whole life. But I thought, “If everybody did that, there wouldn’t be a naturopathic profession.” I am so glad I didn’t go that route, because if you are a medical doctor, you are incredibly hamstrung on what you can do. The naturopathic degree has given me more freedom. It’s a license to get out of my mind, to think any thought possible. To me, that constitutes being a doctor.
I got a tremendous amount from Bastyr; my life now would be impossible without that training. I learned how to chase down a concept, how to navigate scientific literature and how to perform my own versions of meta-analysis. Doctors like Bland, Bastyr, Pizzorno and Mitchell inspired me with the confidence that I had the right to do that as much as anyone else.
But I don’t recommend naturopathy for everybody. If you’re not averse to trying harder in response to futility, if you’re not uncomfortable with failure, and you know that it accompanies any first effort, then this is a good profession for you. But there’s no heroic component here. The Greeks had Asclepius, the god of healing, and Hygeia, the goddess of education and wellness. Masculine and feminine. Asclepius is the surgeon who pulls off the mask and says, “I think I saved his life,” whereas Hygeia states, “This is how you stay healthy, and this is how you learn.” If you identify with Hygeia, then naturopathy is for you. If you want to be Asclepius, then you probably should be a medical doctor.
To be a naturopath, you have to be an autodidact. You have to realize that the education will give you the ability to go and search for knowledge you want to use. If you view the education as the end point, I think you’ll be very sad, because there’s going to be a disconnect. Many of the things you learn in school are useful, but in the real world you have to be flexible. And you have to be very true to your intent, because you spend so much time by yourself.
Part of the art is being an effective small business person. It’s not very artistic, but there is expression there. You can’t be a doctor if you can’t pay an electric bill. The great thing is that there’s no right or wrong. The best solution is to have a profession with a multitude of experts. And the only way to become an expert is to spend a lot of time dealing with the awkward stage that comes from forcing yourself to learn things. That fact leaves me with hope.
Synthesizing the contrasts
In some ways, Peter J. D’Adamo is a study in contrasts. He’s a vegetarian naturopath who recommends eating meat to a number of his patients. He’s written both ballet music and computer software. A clinical researcher, he respects the ethereal nature of naturopathic medicine. He’s a physician whose idea of health care reform is to let the system collapse and replace it with one that educates people to be their own doctors. His sharp wit belies the utter seriousness with which he approaches his work. But at a deeper level, Dr. D’Adamo is really a synthesist. He sees the disparate elements of a puzzle and envisions how they make a whole. While he understands that his theories about inheritance, genes and individualized diet as medicine may be beyond the comfort levels of many naturopaths today, he expects that in another ten years, the profession will welcome his particular means of validating the age-old idea that the body can heal itself naturally.
Author Patty Bates-Ballard is a mother, freelance writer and owner of WordSmooth. Patty's articles have appeared on the Environmental News Network and in Environmental Design + Construction magazine. She has guest lectured at Presbyterian Hospital of Dallas, Sherman's Austin College and El Centro College in Dallas. She works from her home in Dallas, Texas, where she raises her sons, Kory and Kaden.
Reviewed and revised on: 01/12/2023
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